Friction drive transmission



April 5, 1932- F. c. MITCHELL FRICTION DRIVE TRANSMISSION Filed Oct. 10, 1950 3 Sheets-Sheet l INVENTOR E aMi Zeke-LL BY Qq ZASSIW ATTORNEY April 5, 1932- I F. c. MlTCil ELL 1,852,360

FRIG'iION DRIVE 'f RANSMISSION Filed 001:. 10, 1930 S'SheetS-Sheet 2 25 INVENTOR 26 F: U.Mitchell Q Jami ATTORN EV Ap 1932- F. c. MITCHELL 1,852,350

FRICTION DRIVE TRANSMISSION Filed Oct. 10, 1950 5 Sheets-Sheet 3 5 )6 5 10 10a :55 4 1 Q 2 j 5 l V 14 0 l u O lu u iNVENTOR .FI aMifchell BY Q QQAMI...

ATTORNEY Patented Apr. 5, 1932 UNITED STATES PATENT OFFICE.

FLOYD C. MITCHELL, OF STOCKTON, CALIFORNIA, ASSIGNOR TO SUNSET MOTOR COM- PANY, OF SACRAMENTO, CALIFORNIA, A CORPORATION OF NEVADA FRICTION DRIVE TRANSMISSION Application filed October 10, 1930. Serial No. 487,732.

This invention relates topower transmitting devices of the friction drive type as differentiated from one utilizing gears; and particularly relates to transmissions of the general form disclosed in the L. WV. Davls Patents, Nos. 1,107 ,412 dated August 18, 191 i; 1,241,609 dated October 2, 1917; 1,334,- 439 dated March 23, 1920; and 1,633,316 dated June 21, 1927. The present invention also particularly deals with the reversing of the driven cones relative to the driving cones and in this respect represents improvements over the structures shown in the above mentioned patents, though having some points in common with the structure of Patent No. 1,107; 412.

In the general arrangement of the structure of the invention a pair of opposed driving cones are used, fixed on a common drive shaft and arranged to engage oppositely fac ng driven cones arranged between the driving cones. Since the driven cones are connected to a common axle or the like they must both rotate in the same direction and therefore one of such cones must engage one of the driving cones only on one side, while the other driven cone engages the other drlvlng come only on the opposite side. To reverse the d rection of rotation of the driven cones thelr points of contact with the driving cones must be reversed, as will be obvious. In the last mentioned patent this was done by mounting the shafts of the driven cones in eccentric bearings, themselves turnably mounted inbearings on the framework of the transmlsslon, which eccentric hearings were located by a suitable hand actuated lever and linkage mechanism. This arrangement however while enabling the cones to be shifted in a plane at right angles to the drive shaft, so that a full contact with the driving cones was always made, either provided to limit a range of shifting movement, or else caused the center to center distance between the cone shaftsand the axle to be altered. Since these shafts are connected to each other by chain or gear drives, this relative altering of the center to center distance resulted in poor working of the gears or chains. In the other patents the cone reversing arrangement was such that the cones did not engage each other evenly for the full width of their faces'and a break-down of the cones soon resulted.

It is therefore the main object of the present invention to provide a reverse arrangement for the driven cones of such a nature that said cones will move in a plane parallel to the drive shaft, while at the same time the shafts on which the driven cones are mounted will always remain at a constant center to center distance from the axle to which said shafts are operatively connected.

The objectionable features and defects inherent in the previous constructions are therefore eliminated.

I have also provided a manually operated mechanism for thus shifting or reversing the cones so that the engaging pressures of the drlven cones with the driving cones Will be equalized, regardless of any inequalities in wear and consequent difference in size of the opposed cones.

These objects I accomplish by means of such structure and relative arrangement of parts as will fullyappcar by a perusal of the following specification and claims.

In the drawings similar characters of ref erence indicate corresponding parts in the several views: a a

Fig. is a perspective view of my improved transmission structure as arranged in unitary association with a power plant.

Fig.2 is an enlarged transverse section of the structure. a

Fig. 3 is a top plan view of the same.

Fig. 4: is an enlarged fragmentary view of the manually actuated shifting apparatus, showing the pressure equalizing mechanism thereof.

Referring now more particularly to the characters of reference on the drawings, the numeral 1 denotes suitably spaced side frames which form the support for the transmission and preferably but not necessarily for a power plant such as a gas engine 2. Extending lengthwise of and above the plane of the frames is a drive shaft 3, which in a closely coupled arrangement, is a direct extension of the engine shaft, and apart from the engine journals is only supported at its end opposite the engine in a bearing 4 mounted on a cross beam 1a secured to the frames 1. Splined or slidably keyed on the shaft are opposed driving cones 5 arranged in facing relation to each other. Projecting between these cones are the driven cones 6 also arranged in facing relation toeach other. These driven cones are splined or slidably keyed on separate shafts 7 arranged in a horizontal-plane at rightangles tothe plane of the shaft'Sihut normally out of-longitud-inal alinement with each other,.althoughparallel as shown in Fig. 3. Therefore since the cones 6 are the same size oneof suchcones engage one of the cones 5 only, while the other conefi will engage the other cone 5 onlyand inrerersed. oropposed order. Both cones 6 will therefore rotate in the same direction. Shifting of the shafts '1'. horizontally in a plane transversely of their length and in opposite directions simultaneously, will reverse the. engagement of the conesv Gwith the cones 5. and the. mechanismfor accomplishing this result forms the main. feature of the present .inventiomas will now be described.

' Disposed directly under the frames 1 parallel to the shafts 7: is. an. axle 8.. or the. like, on the. outer. end: of which, wheels are adapted to. be mounted. In certain cases, this axle may be a one-piece member, but, fort-ractor and other service, it ispreferably formed of two separate independently turnable parts, as shown. A sleeve 9; surrounds the axle under the transmission structure. Intermediate its ends; the. sleeve is engaged by the lower ends Ofiseparate-yerticaliarms 10; which extend upwardly past the shaft 3 in surrounding but i-ioinengaging relationship therewith, as

shQ-wninEig. 2, and are formed intermediate their ends with bearing bosses orhousings 10a for the adjacent ends of. they shafts 7. its outer end saidisleeve 9 projects into the hubs 1:1; ofwgear. boxes.12;,. which also in effect constitute arms and which project upwardlyandare provided: at; their upper ends wit-l bearings for the outerends of the corresponding shaft-s 7 Extension arms 13 are rigidnvith, and: project upwardly from the housings or gear boxes l2 to a. height. equal to thatof the arms .10. Bearing members 14 secured to and. depending from the frames 1 engagethe hubs, 11 ofthe housings and thus pivotal- 1y support said housings; the axle members being journaled in the hubs-11. Trains ofgearing or the like indicated at 15 and enclosed, in thehousings 12 operatively connect the shafts 7 andtheaxlein driving relation, and it will be seen that the distance between the centers of saidshafts and-the axle u always remains constant irrespective ofv the rocking of esings It will also be'seen that withsuchrocking the shafts 7; are maintainedin aplane at; right angles to theshaftB; v

1 Simultaneousshifting movement is. impart.-

ed to the shafts 7 in opposite directions by the following means: Disposed beyond one end of the transmission in transversely alined relation therewith are a pair of longitudinally alined shafts 16, preferably on a level with the upper ends of the arms lOand 13. These shafts are journaled in'bea rings 17 having braelget plates 18 by means of which they may b mo nted. in. a fixe p si o I e P165: ent instance these plates are shown a's-being mounted on the flywheel housing of the engine, but this isa matter of convenience and depends on thelocation desired for the operating-lever 19.. This lever is turnably mounted on the shafts 16 at their adjacent ends and projects upwardly to a convenient height. Fixed: on said'shaftsitothe side of theslever are sleeves 20 from which posts 21, parallel tothe lever, project upwardly. Turnahlse on vertical pins 22 upstanding from: the. .posts is a bar 23 extending between the pins; and passing freely through a slot Siin the lever. Fron'i one sleeve and from thecor'responding shaf beyond the same short arms 24 project upwardly, while from the. other sleeye and fromthe corresponding shaft other armslg25 of the same length depend. These; pairs of arms are longitudinally alined with theipairs OLE-QIIDS L0 and: 13- andare. connected thereto by rigid pivoted'links'26z. lit will thus beseen that by this arrangement a movement of' thle lever will impart: a movement; in the samefdirection to both shafts 16. .On accountoifi the pairs of arms 2% andz25 extending; opposite directions radially of'the shaft however, one pair of arms 10 and l3 and the correspondr i-ng shaft 7 will. be moved in. one. direction, and. the. other. pair of arms. and thecorresponding shaft. 7 will be moved in the opposite direction.

- it will also beseen by reason oftheeqtialiizing bar 23. that if one cone.6:should engage its cone 5.. before. the. other cone; =6 .mages'. its cone 5, a movement will: stillxbe impartedvto the control mechanism. of said: other conel by a continued movement of theleuer, soathat the final; engagingpressure ofethe cooperating coneswill 'beiequala- Since this. apparatus. is a change.speedtransmission, asiwellas aforward; and reverse speed; arrangement; means is providedztoislide the pairs OfCODQSlGlEt/lVG te each other inn-opposite directions, so assto alter their 'relatlye diameters as far astheir areas ofcont-act at any onetime.isconcerned; This isaccomplished. by the same structure usedin the previous. patents, as shownirt the drawings andcontrolled by. alever. .ZTpref erably mountedin connection withtheshafts 1.6 but of course having; no .connectiontherewith. Since this. arrangement however-forms nopartsof the presentii-nvention\adescniption of the same is-deemed unnecessary. It isto be noted that.th'e-equalizer struetnr isnot. necessary or even-.- desirable inv certain cases, (as in tractor serviceifor. quick turning of the tractor) and the rotation of the shafts 16 would then be separately controlled.

From the foregoing description it will'be readily seen that I have produced such a device as will substantially fulfill the objects of the invention as set forth herein.

While this specification sets forth in detail the present and preferred construction of the device, still in practice such deviations from such detail may be resorted to as do not form a departure from the spirit of the invention, as defined by the appended claims.

Having thus described my invention what I claim as new and useful and desire to secure by Letters Patent is:

1. In a friction drive structure having oppositely arranged and cooperating pairs of drive and driven friction members, separate shafts on which said driven members are mounted, a wheel-supporting axle unit parallel to said shafts mounted in fixed vertically spaced relation thereto, a pair of spaced arm members for each shaft turnably mounted on the axle unit, bearings for the shafts in the corresponding arms, drive connections between each shaft and the axle unit, and means applied to the arms for rocking the same simultaneously about the axle unit but in opposite directions.

2. In a friction drive structure having oppositely arranged and cooperating pairs of drive and driven friction members, separate shafts on which said driven members are mounted, a wheel-supporting axle unit parallel to said shafts mounted in fixed and spaced relation thereto, a pair of spaced arm members for each shaft turnably mounted on the axle unit, bearings for the shafts in the corresponding arms, one of each pair of arms being formed as a housing surrounding the axle unit and corresponding shaft, drive connections between the shafts and axle unit enclosed within the corresponding housing, and means for rocking the arms simultaneously but in opposite directions about the axle unit as an axls.

3. In a friction drive structure having oppositely arranged and cooperating pairs of drive and driven friction members, separate shafts on which said driven members are mounted, and vertical rocking arms on which said shafts are supported; a means for rocking the arms of the separate shafts simultaneously but in opposite directions and with equalized pressure comprising separate shafts parallel to said first named shafts and spaced horizontally from the arms, posts fixed in connection with said separate shafts in parallel relation radially thereof, a cross-bar between the outer ends of the posts and pivotally mounted thereon, a lever turnably mounted axially of said separate shafts between the posts, said lever having a slot through which the bar freely projects, and connecting instrumentalities between the separate shafts and the separate shaft sup porting arms for rocking the latter in opposite directions with a rotation of said separate shafts in a common direction.

In testimony whereof I aifix my signature.

FLOYD C. MITCHELL. 

